The invention relates to metering guns or nozzles for dispensing a lubricating fluid.
In the field of vehicle service, handheld metering guns or nozzles are used to dispense predetermined amounts of lubricating fluids, such as oil. These devices have a lever that is squeezed against a handle to begin operation. A metering portion of the device then measures the amount of fluid passing through the device and closes a valve when a preset amount of the fluid has been dispensed. Such devices are useful in servicing vehicles using bulk supplies of oil or other lubricants, and are also useful in other industrial applications.
An example of such a device is disclosed in Fehl et al., U.S. patent application Ser. No. 09/595,829 filed Jun. 16, 2000 and now allowed. In this device a programming keypad is integrated with a lube meter for metering the dispensing of oil or other lubricants.
There is, however, a problem associated with allowing such devices to be used in a standalone mode, in that the device could be operated before a meter is started to measure the dispensed lubricants. Thus, oil or other fluids might be dispensed without being accounted for. Furthermore, because each device is programmed and operated by an individual user, it can be difficult to maintain uniform control over the amount of fluid dispensed at a service station or facility.
U.S. Pat. No. 5,941,418 discloses a system in which multiple lubrication meters are controlled by a control pendant. In this system the pendant is used for the purpose of the keypad already integrated in the device of Fehl et al., cited above. Here, the lubrication meters are linked together through a twisted-pair network. The pendant can be coupled to any of the lubricating meters for the purpose of programming the system and ordering the dispensation of fluids.
While this system provides some advantages in monitoring and controlling overall fluid delivery, however, this system also presents a number of disadvantages. For example, the twisted pair network requires a large amount of network infrastructure in the service facility, and limits the ability to move the lubricating meters to suit the size and location of vehicles, containers, or other equipment to be serviced. Furthermore, the system cannot be controlled from a central office or location unless the twisted pair network is wired additionally to the central location.
There is a need in the art to provide a flexible system for automatically controlling dispensing lubricants from one or more handheld metering device, and for ensuring that programmed batches are dispensed and accounted for.
The invention is incorporated in a method and device for dispensing a lubricating fluid, in which the device is held in a disabled state until an enable signal is received from a master control station, thereby protecting the device from dispensing lubricant that is not metered. After the enable signal is received, a programmed batch is dispensed and, when completed, the operator hits a reset button to signal completion of the first batch and set up for the next enable signal for the next batch.
More specifically, the invention comprises a method of controlling the dispensing of an amount of lubricant by a dispensing apparatus. A valve is blocked until an enable signal is received from a control station. Upon receipt of the enable signal, the valve can be manually actuated from a closed to an open position. After manual actuation, the valve is latched in the open position, and a parameter of the flow of the liquid is measured until the parameter equals a preset amount. An electrically operable device is then activated to unlatch the valve, and the valve is allowed to return to a closed position, wherein the flow of liquid is stopped, and a signal is generated and transmitted to the control station indicating that the batch preset amount has been dispensed. Upon receipt of a signal from the control station, the valve is again blocked from operation until the next enable signal is received.
It is an object of the invention to provide a lubricant dispensing system comprising a central control station and one or more handheld metering devices which communicate through a wireless communications network, and particularly through an RF communications network.
It is another object of the invention to provide a lubricant dispensing system wherein a preset amount of lubricant to be dispensed can be selected at a central control station.
It is yet another object of the invention to provide a lubricant dispensing system including a latch which can lock the dispensing or metering device in both an open and a closed positions.
It is yet another object of the invention to provide a lubricant dispensing system wherein the central control station is capable of providing an override signal, wherein upon receipt of the override signal, the handheld metering device latches the valve in the closed position.
It is still another object of the invention to provide a multi-piece valve assembly, wherein interaction between a start actuator piece positioned between an actuating lever and the valve member and a latching pin prevents leak-though from the valve when the valve is in a locked closed position.
It is another object of the invention to provide some play in the manually-actuated lever to prevent overstressing of the lever. The play provides manual feedback to the user when the lever is disabled from operation indicating that the lever is blocked.
Other objects and advantages of the invention, besides those discussed above, will be apparent to those of ordinary skill in the art from the description of the preferred embodiments which follow. In the description, reference is made to the accompanying drawings, which form a part hereof, and which illustrate examples of the invention. Such examples, however, are not exhaustive of the various embodiments of the invention, and therefore, reference is made to the claims which follow the description for determining the scope of the invention.